1. Field of the Invention
The invention relates to a microfluidic device including a microfluidic chip and a shape memory substrate attached to the microfluidic chip for creating a temporary vacuum to induce fluid flow within the microfluidic chip.
2. Description of the Related Art
Conventional microfluidic devices require external driving means to transport a liquid into or out of a microfluid channel in the microfluidic device, which complicates the assembly of the microfluidic device and the external driving means. In addition, most external driving means are incompatible with microfluidic devices for biochemical applications.
U.S. Patent Application Publication No. 2006/0036045 discloses a valve actuator of a shape memory polymer. The valve actuator is operable to block the flow of a fluid in a fluid passage. The shape memory polymer can be transformed into a different shape by heating using laser or a resistive-type heater.
U.S. Patent Publication No. 2005/0212630 discloses a shape memory polymer containing magnetic particles. The shape memory polymer can be heated by applying an alternate magnetic field to the magnetic particles. The energy of the alternate magnetic field is converted into heat through magnetic hysteresis loss of the magnetic particles.
The entire disclosure of U.S. Patent Application Publication No. 2005/0212630 is incorporated herein by reference.